Silicone oil has excellent lubricating properties, water repellency, gloss-imparting property, shelf stability and safety and as such is used widely as a cosmetic base.
However, high molecular weight dimethylpolysiloxanes, one of the silicone oils which is most commonly in use, is sparingly soluble in polar oils and water and is hardly emulsifiable in hydrocarbon oil-containing systems. Furthermore, cosmetic products containing this silicone oil and other silicone oils give characteristic "squeak" and thus are unsatisfactory in feel.
There has, accordingly, been a long-standing demand for the development of a silicone derivative which insures an improved feeling in use which the conventional silicone oils lack.
Under these circumstances the inventors of the present invention explored the above problem and found that an ester-modified silicone derivative of formula (I) shown below is highly compatible with hydrocarbon oils, polar oils, water, etc., and remains stable in systems containing the same and further that cosmetic formulations including this compound does not give "squeak", thus offering an improved feeling in use. The present invention is based on the above finding.